Medium processing device and medium conveying unit

Abstract

A medium processing device includes: a conveying portion configured to convey a medium along a conveyance path; and a medium processing portion. The conveyance path includes: an upstream path; a downstream path; and a merging path including a processing position. The conveying portion includes a first roller pair arranged on the downstream path and a second roller arranged on the merging path. The first roller pair is configured to be set to a nip state during execution of a conveying operation to convey the medium from the merging path toward the downstream path. The first roller pair is configured to be set to a nip release state during execution of a medium processing operation while the medium is positioned at a nip position of the first roller pair.

What is claimed is: 
     
         1 . A medium processing device comprising:
 a conveying portion configured to convey a medium along a conveyance path;   a medium processing portion configured to process the medium conveyed by the conveying portion; and   a controller configured to control the conveying portion and the medium processing portion,   wherein the conveyance path comprises:
 an upstream path; 
 a downstream path; and 
 a merging path on which the upstream path and the downstream path are to be merged, the merging path comprising a processing position at which the medium is processed by the medium processing portion, 
   wherein the conveying portion comprises a first roller pair arranged on the downstream path and a second roller arranged on the merging path,   wherein the controller is configured to execute:
 a medium processing operation to cause the medium processing portion to process the medium while rotating the second roller to convey the medium in a state in which the medium is positioned over the merging path and the downstream path; and 
 a conveying operation to cause the first roller pair to rotate to convey the medium from the merging path toward the downstream path, 
   wherein the first roller pair is configured to be set to a nip state during execution of the conveying operation, and   wherein the first roller pair is configured to be set to a nip release state in which a nip force is smaller than that in the nip state during execution of the medium processing operation while the medium is positioned at a nip position of the first roller pair.   
     
     
         2 . The medium processing device according to  claim 1 , wherein the nip release state is a state in which two rollers forming the first roller pair are separated from each other. 
     
     
         3 . The medium processing device according to  claim 1 , wherein the controller is configured to convey, in the medium processing operation, the medium in a direction from the merging path toward the downstream path and a direction from the downstream path toward the merging path. 
     
     
         4 . The medium processing device according to  claim 3 , wherein the medium processing portion is configured to cut the medium. 
     
     
         5 . The medium processing device according to  claim 1 ,
 wherein the conveying portion comprises:
 a third roller arranged on the upstream path; 
 a first conveying motor configured to rotate the first roller pair and the third roller; and 
 a second conveying motor configured to rotate the second roller, and 
   wherein the first roller pair is configured to selectively taking the nip state or the nip release state in accordance with driving of the first conveying motor.   
     
     
         6 . The medium processing device according to  claim 5 ,
 wherein the first roller pair comprises:
 a fourth roller; and 
 a fifth roller located to sandwich the fourth roller between the fifth roller and the upstream path, and 
   wherein the fourth roller is configured to move in a direction approaching the upstream path when the first roller pair shifts from the nip state to the nip release state.   
     
     
         7 . The medium processing device according to  claim 1 , wherein the controller is configured to shift the first roller pair from the nip state to the nip release state before the medium processing operation starts. 
     
     
         8 . The medium processing device according to  claim 1 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         9 . The medium processing device according to  claim 2 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         10 . The medium processing device according to  claim 3 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         11 . The medium processing device according to  claim 4 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         12 . The medium processing device according to  claim 5 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         13 . The medium processing device according to  claim 6 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         14 . The medium processing device according to  claim 7 , wherein the controller is configured to shift the first roller pair from the nip release state to the nip state after the medium processing operation ends and before the conveying operation starts. 
     
     
         15 . A medium conveying unit comprising:
 a first conveying portion configured to convey a medium along an upstream path and a downstream path; and   a controller configured to control the first conveying portion,   wherein the medium conveying unit is configured to be attached to a medium processing unit, the medium processing unit comprising a second conveying portion configured to convey the medium along a merging path on which the upstream path and the downstream path are to be merged, and a medium processing portion configured to process the medium conveyed by the second conveying portion at a processing position provided on the merging path,   wherein the first conveying portion comprises a first roller pair arranged on the downstream path,   wherein the second conveying portion comprises a second roller arranged on the merging path,   wherein the controller is configured to execute a conveying operation to cause the first roller pair to rotate to convey the medium from the merging path toward the downstream path,   wherein the first roller pair is configured to be set to a nip state during execution of the conveying operation, and   wherein the first roller pair is configured to be set to a nip release state in which a nip force is smaller than that in the nip state during execution of a medium processing operation while the medium is positioned at a nip position of the first roller pair, the medium processing operation being executed to cause the medium processing portion to process the medium while rotating the second roller to convey the medium in a state in which the medium is positioned over the merging path and the downstream path.   
     
     
         16 . A medium conveying unit configured to be attached to a medium processing unit, the medium conveying unit comprising:
 a first roller pair configured to convey a medium processed by the medium processing unit; and   a third roller configured to convey the medium toward the medium processing unit,   wherein the first roller pair is configured to selectively taking a nip state or a nip release state in which a nip force is smaller than that in the nip state.